It is common in spinal surgery to perform a two incision operation, with implants placed from the front (i.e. anterior) portion of the vertebral column and supplemental fixation placed from the back (i.e. posterior) portion of the vertebral column. This effectively creates fixation in all three columns of the spine, and, hence, superior stabilization. The three columns of the spine—anterior 10, middle 12, and posterior 14—are shown in FIG. 1. To create a stable, solid fusion, a surgeon typically needs to stabilize all three columns in order to prevent micro-motion from occurring, which can lead to non-union of the segment (i.e. pseudoarthrosis).
To accomplish this, the surgeon frequently utilizes two different surgical approaches (anterior and posterior) and two separate spinal systems to achieve a stable construct. This is done using an Anterior Lumbar Interbody Fusion (ALIF) cage, with or without supplemental screws, via the anterior approach, and then using posterior pedicle screws or facet screws from the back of the patient. The surgeon performs an anterior discectomy and places the ALIF cage into the front disc space, and may secure it with screws into the vertebrae. Then the surgeon flips the patient over and places the screws from the back. This posterior approach is time consuming, technically challenging, and, for accuracy, sometimes it is robotically assisted to minimize the risk of nerve injury.
Thus, truly unified three column spinal fixation implants and associated surgical methods operable for simultaneously anteriorly and posteriorly stabilizing a portion of the spine at a given level are still needed in the art.